Nozzle structure of fuel injector for internal combustion engine

摘要

A fuel injector for an internal combustion engine is provided which includes a valve body, a needle valve, and a hollow nozzle body with a bottom having formed therein spray holes. The needle valve is controlled to be selectively brought into and out of engagement with a valve seat in the valve body to close and open a fuel outlet formed in an end surface of the valve body. The hollow nozzle body is welded to the valve body with the bottom urged into constant engagement with the end surface of the valve body at a given level of pressure which is greater than a maximum fuel injection pressure. This makes it possible to establish the constant engagement of the bottom of the hollow nozzle body with the end surface of the valve body without any clearances even when the maximum fuel injection pressure acts on a portion of the bottom of the hollow nozzle body around the spray holes.